Although a brush motor was used in an air conditioning device for rotating and driving an impeller generating an air flow, a brushless motor is used in recent years. Since a blower motor for HVAC has high output power, an anti-heating measure is necessary to improve the motor efficiency.
Since the motor part and the motor board are assembled as separate bodies in the case of a brush DC motor, a part of air blown by the impeller flows in from an exhaust port called a cooling channel and the air is blown to the entire motor for cooling.
However, since the motor part and the motor board having a motor driving circuit are integrally assembled in the case of a brushless motor, it is not possible to cool only the motor part.
Accordingly, there is proposed an air conditioning device in which the heat generated in a motor control apparatus is radiated to air passing through a heat sink and the heat is radiated to air for cooling the motor and a yoke (see PTL 1: JP-A-2008-207645).